通过氧化5,5',6,6'-四羟基-2,4'-联吲哚得到的首个5,6-二羟基吲哚四聚体以及在合成真黑素相关聚合物过程中出现的意想不到的位置反应性问题。

The first 5,6-dihydroxyindole tetramer by oxidation of 5,5',6,6'-tetrahydroxy- 2,4'-biindolyl and an unexpected issue of positional reactivity en route to eumelanin-related polymers.

作者信息

Panzella Lucia, Pezzella Alessandro, Napolitano Alessandra, d'Ischia Marco

机构信息

Department of Organic Chemistry and Biochemistry, University of Naples Federico II, Via Cinthia, I-80126 Naples, Italy.

出版信息

Org Lett. 2007 Mar 29;9(7):1411-4. doi: 10.1021/ol070268w. Epub 2007 Mar 9.

DOI:10.1021/ol070268w

PMID:17346057

Abstract

[structure: see text]. The first tetramer of the eumelanin precursor 5,6-dihydroxyindole has been obtained, as the acetyl derivative, by peroxidase/H2O2-induced oxidative coupling of 5,5',6,6'-tetrahydroxy-2,4'-biindolyl (2) in the presence of Zn2+ ions. The tetramer, 5,5',5'',5''',6,6',6'',6'''-octaacetoxy-2,4':2',3'':2'',4'''-tetraindolyl (acetylated 7), incorporates an unprecedented 2,3'-biindolyl substructure suggestive of a different positional reactivity of the 5,6-dihydroxyindole system when framed into a dimeric scaffold.

摘要

[结构：见正文]。通过在锌离子存在下，过氧化物酶/H₂O₂诱导5,5',6,6'-四羟基-2,4'-联吲哚（2）的氧化偶联反应，首次获得了真黑素前体5,6-二羟基吲哚的四聚体，即乙酰衍生物。该四聚体5,5',5'',5''',6,6',6'',6'''-八乙酰氧基-2,4':2',3'':2'',4'''-四吲哚基（乙酰化的7）包含一个前所未有的2,3'-联吲哚基亚结构，这表明当5,6-二羟基吲哚体系构建成二聚体支架时，其位置反应性不同。